Editing String (computer science) (section)

==== Byte- and bit-terminated ====
Using a special byte other than null for terminating strings has historically appeared in both hardware and software, though sometimes with a value that was also a printing character. <code>$</code> was used by many assembler systems, <code>:</code> used by [[Control Data Corporation|CDC]] systems (this character had a value of zero), and the [[ZX80]] used <code>"</code><ref name=asm>{{cite web|last1=Wearmouth |first1=Geoff |title=An Assembly Listing of the ROM of the Sinclair ZX80 |url=http://www.wearmouth.demon.co.uk/zx80.htm |url-status=unfit |archive-url=https://web.archive.org/web/20150815035611/http://www.wearmouth.demon.co.uk/zx80.htm |archive-date=August 15, 2015 }}</ref> since this was the string delimiter in its BASIC language.

Somewhat similar, "data processing" machines like the [[IBM 1401]] used a special [[Word mark (computer hardware)|word mark]] bit to delimit strings at the left, where the operation would start at the right. This bit had to be clear in all other parts of the string. This meant that, while the IBM 1401 had a seven-bit word, almost no-one ever thought to use this as a feature, and override the assignment of the seventh bit to (for example) handle ASCII codes.

Early microcomputer software relied upon the fact that ASCII codes do not use the high-order bit, and set it to indicate the end of a string. It must be reset to 0 prior to output.<ref>{{cite web |last1=Allison |first1=Dennis |title=Design Notes for Tiny BASIC |url=http://www.ittybittycomputers.com/IttyBitty/TinyBasic/DDJ1/Design.html |url-status=live |archive-url=https://web.archive.org/web/20170410220759/http://www.ittybittycomputers.com/IttyBitty/TinyBasic/DDJ1/Design.html |archive-date=2017-04-10 }}</ref>